Your 500m pace from rep to rep must get faster and faster. Your 500m pace from round to round must also get faster and faster. As example, your 500m pace from 1000m to 500m to 250m (as well as each subsequent round) must get faster and faster. In addition, your 500m pace from 1000m to 800m to 600m to 400m to 200m must get faster and faster. This means the 1000m pace is the slowest and the 100m pace is the fastest. Reset your rower after every interval. Use a second clock to maintain your rest.